In wireless communication systems, a base station is an equipment for providing services to a terminal, and the base station communicates with a terminal via up direction/down direction links, wherein the up direction refers to a direction from the terminal to the base station, and the down direction refers to a direction from the base station to the terminal. Multiple terminals can simultaneously send data to the base station via the uplink and can simultaneously receive data from the base station via the downlink as well. In wireless communication systems which adopt the base station to realize the scheduling and control of wireless resources, the scheduling and allocation of the wireless resources of the system are carried out by the base station, for example, the base station provides resource allocation information when the base station performs transmission, resource allocation information which can be used when the terminal performs uplink transmission, and etc.
In commercial wireless communication systems, when the base station is scheduling wireless resources of an air interface, generally one wireless frame is taken as one scheduling period, and one wireless frame is divided into several resource units of the same size (for example, one time slot and one code word) to perform scheduling. During the scheduling period, the base station can schedule all the resources within the wireless frame and provide data or multimedia services to all terminals covered by the base station. For example, in 2G wireless communication systems with GSM (Global System for Mobile Communication) as a representative, the base station divides the wireless resources at each frequency point into one TDMA (Time Division Multiple Access) wireless frame of 4.615 ms, and each wireless frame comprises 8 identical time slots, wherein one time slot can transmit one full rate call or two half rate calls, and can also realize low rate data services. In 2.5G wireless communication systems with GPRS (General Packet Radio Service) as a representative, by introducing packet switching which is performed based on a fixed time slot, the rate of data services can be enhanced up to above 100 kbps, while they still can not support multimedia services such as video. In 3G wireless communication systems with TD-SCDMA (Time-Division Synchronization Code Division Multiple Access) as a representative, the base station likewise divides the wireless resources of the air interface into wireless frames with a period of 10 ms, and each wireless frame comprises 14 normal time slots and 6 special time slots, wherein the normal time slots are used to transmit specific services and signalings, and the base station distinguishes users by different code words on each normal time slot.
With the fast development of communication technologies, the commercial wireless communication systems are unable to meet the user's demands of high transmission rate, high-speed motion and low time delay, which are reflected in increasingly growing demands on high speed data and fluent multimedia services, and this also raises new requirements and challenges for the design of future wireless communication systems.
Future wireless communication systems, with an LTE (Long Term Evolution) system, a UMB (Ultra Mobile Broadband) and IEEE 802.16m as representatives, use OFDM (Orthogonal Frequency Division Multiplexing) and OFDMA (Orthogonal Frequency Division Multiple Address) technologies, and thus make the possibility of high rate transmission. However, at the same time, it imposes new restraints on wireless resource management and raises the demands on future wireless communication systems as follows.
1. With the increase of communication service traffic, the system bandwidth taken up by the future wireless communication systems becomes wider and wider, and at the same time it requires that the future wireless communication systems support different system bandwidths so as to support terminals of different types or abilities;
2. With the increasingly tighter future wireless frequency spectrum resources, it is required that future wireless communication systems should support multi-carrier operations, in order to fully use scattered frequency band resources.
3. As there will be more and more service types to be supported in the future, different types of services have different demands on the QoS (Quality of Service) and on wireless resource units, especially a VoIP (Voice over Internet Protocol) data packet and small control-type messages.
4. The frame structure and control channel of future wireless communication have higher requirements on wireless resource management.
It can be seen that the current wireless resource units (such as time slots and code words) and their corresponding sub-channelization and resource mapping procedure have already become unable to fully meet the demands of the future wireless communication systems. To assure the frequency spectrum efficiency for the future wireless communication systems, it is necessary to design a new method for sub-channelization and resource mapping of wireless resources.